The present invention is directed to household appliances. More particularly, the present invention relates to safety arrangements for locking devices serving to close containers of cooking mixers.
Conventional mixers, in order to assure the safety of the device during operation, include control contactors or motor controllers connected into the motor current circuit. These motor contactors serve to shut down the motor when the container is mechanically unlatched, so that a user cannot accidentally come in contact with the moving mixer blades or, if the container has been detached, with the rotating coupling which drives the mixer blades.
However, in the type of mixer which also cooks the contents, this kind of construction has certain disadvantages. Since the container is almost airtight the heating of food in the container causes a slight internal overpressure. When the closure of the container is unlatched the motor is disconnected, at the same time. For a brief time period thereafter the liquid or other contents of the mixer then continue to be mixed and to rotate in the container, and since the closure is no longer held tightly closed the liquid, aided by the overpressure, may run out of the container. This can lead to burn injuries for the user.